Introduction
Most maintenance teams know they need flow measurement on their compressed air lines. But getting that data often requires shutting down production—and finding a shutdown window is the problem that never gets solved.
So flow monitoring stays on the “someday” list.
WiseAir’s WAFS 104 addresses this specific barrier. It’s an insertion-type thermal mass flow sensor designed to install under pressure, directly into an active pipeline through a ball valve. No shutdown. No complex installation. No waiting for a maintenance window that never comes.
How WAFS 104 Installation Works
The WAFS 104 is installed as a hot-tap insertion sensor through a safely prepared, pressure-tight ½-inch ball valve connection. Installation must be performed by qualified personnel in accordance with the user manual.
This approach works for pipe sizes from DN20 to DN300, covering most compressed air distribution systems.
Installation timeline: Typically site-dependent, ranging from 15–30 minutes under optimal conditions, versus 4–8 hours for traditional inline sensors that require pipe cutting and welding.
Thermal Mass Flow Measurement: What It Means
The WAFS 104 measures mass flow directly using thermal mass flow principle. This has a specific advantage:
Traditional flow sensors (differential pressure, turbine) measure volume, then require separate pressure and temperature measurement to calculate actual mass flow. This adds complexity—more hardware, more calibration points, more potential failure points.
The WAFS 104 is designed to provide mass flow measurement with reduced dependency on separate pressure and temperature compensation. The thermal principle accounts for these variables inherently, allowing your consumption data to reflect mass flow more directly regardless of line pressure fluctuations or ambient temperature variation.
Key Measurement Characteristics
High-Resolution Data Capture
The sensor provides continuous measurement of flow, velocity, and temperature. This allows you to identify consumption patterns, demand variations, and abnormal behavior in your compressed air system.
With continuous monitoring, you see true consumption patterns rather than averaged numbers that hide short-term variations. This is critical when evaluating whether a compressor is truly undersized or oversized.
Multi-Gas Capability
The WAFS 104 measures compressed air, nitrogen, argon, and other inert technical gases. For plants with mixed utility monitoring needs, this provides consistent measurement across different gas types.
Technical Specifications – WAFS 104 Series
Core Specifications:
| Specification | Detail |
| Measurement Type | Thermal Mass Flow |
| Principle | Direct mass flow; reduced dependency on separate P/T compensation |
| Pipe Size Range | DN20–DN300 |
| Installation | Hot-tap insertion through ½” ball valve (qualified personnel required) |
| Accuracy | ±(1% of reading + 0.3% of full scale) |
| Measurement Range | 0.1–250 Nm/s |
Output & Integration:
| Specification | Detail |
| Outputs | 4-20 mA analog or Modbus RTU digital |
| Power Supply | 18–30 VDC, 5 W |
| Calibration Interval | At least every two years |
Environmental Ratings:
| Specification | Detail |
| Pressure Rating | 0–5.0 MPa (installation device required above 1.6 MPa) |
| Operating Temperature | −30°C to +70°C |
| Medium Temperature | −40°C to +150°C |
Installation Comparison: Insertion vs. Inline
| Factor | Inline Sensor | WAFS 104 Insertion |
| Installation | Pipe cutting, welding | Hot-tap through ball valve |
| Downtime | 4–8 hours | Site-dependent (typically brief) |
| Scheduling | Requires planned window | Requires qualified personnel |
| Flexibility | Permanent | Removable/relocatable |
What This Sensor Provides
- Actual flow data at specific points in your compressed air system
- Continuous consumption monitoring without interrupting production
- Data for identifying waste and abnormal consumption patterns
- Information to support compressor capacity decisions
- Audit trail of compressed air usage
Practical Applications
Consumption Monitoring
Track how much compressed air each production area uses. Identify peak demand drivers.
Leak Detection
Abnormal consumption spikes in continuous flow data can indicate developing leaks.
Compressor Evaluation
Compare actual peak consumption to compressor specifications. Determine if sizing is appropriate.
Shift-Based Analysis
Understand consumption pattern differences between production shifts. Identify optimization opportunities.
System Optimization
Monitor pressure drops and flow variations across different times. Make infrastructure adjustments based on real data.
Read More : https://www.wiseair.in/compressed-air-audit-guide-india/
Integration with Broader Monitoring
The WAFS 104 is most useful as part of a complete monitoring system:
- WAFS 104 Flow Sensor — Consumption measurement at specific points
- WADS Series Dew Point Sensors — Air quality monitoring
- WAPS Series Pressure Sensors — Pressure stability tracking
- WAPM Series Power Meters — Energy cost correlation
Together these provide comprehensive visibility: consumption amount, location, air quality, and associated energy costs.
When to Consider This Sensor
The WAFS 104 is suitable for:
- Plants where production shutdown creates scheduling conflicts
- Systems with pipe sizes DN20 to DN300
- Applications requiring multi-gas measurement capability
- Operations needing consumption trend data
- Facilities requiring audit-ready flow documentation
Installation Requirements
Installation must be performed by qualified personnel in accordance with the user manual.
Standard Process:
- Identify measurement point on compressed air line
- Install properly prepared, pressure-tight ½” ball valve
- Insert WAFS 104 probe through valve under qualified supervision
- Connect output (4-20 mA or Modbus)
- Begin data collection
No production shutdown required. Setup time varies based on site conditions.
If you need flow measurement on your compressed air system but have been unable to fit installation into your production schedule, contact WiseAir for a system review.
We can help identify the best measurement points for your operation and coordinate installation with qualified personnel.
📞 Call: +91 90477 78715
📧 Email: info@wiseair.in
🌐 Website: www.wiseair.in


